首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
Because of the shortage of human skin for research purposes, porcine skin has been used as a model of human skin. The aim of this study was to identify the region of German Landrace pig skin that could be used as the best possible substitute for human abdominal skin. Porcine samples were collected from the ear, flank, back and caudal abdomen; human abdominal skin samples were excised during plastic surgery. Histological and ultrastructural assessments were carried out on the epidermis and dermis, with emphasis on the dermo‐epidermal interface length, dermo‐epidermal thickness ratio as well as densities of; hair follicles, arrector pili muscles, blood vessels and sweat glands. In the pig, the barrier function of the four anatomical regions was assessed. Results showed that both histologically and ultrastructurally, all four regions of porcine skin were similar to human skin. These include the shapes of keratinocytes, structure of cell contacts and presence of Weibel Palade bodies in endothelial cells. Other parameters such as the thickness of epidermis, the thickness of stratum basale, spinosum and granulosum and the number of cell layers in the stratum corneum were similar in human abdominal and in all four regions of porcine skin. However, there were also significant differences especially in the thickness of the stratum corneum, the dermo‐epidermal interface length and the blood vessel density.  相似文献   

3.
The vascular bed of the rabbit ear has been studied with light microscopy, microangiography and scanning electron microscopy of resin casts in a series of 20 ears. The major arteries supplying the ear were the central and rostral auricular branches of the caudal auricular artery. The caudal auricular branch was not observed, except as a small vessel supplying the rostral auricular base. The central auricular branch supplied blood to most of the auricular integument and was surrounded by capillaries extended from those supplying the skin. The periarterial capillaries formed a fine, compact network in the tunica media and were closely related to the central auricular branch. Evidence is presented suggesting that this vascular mechanism has a counter-current heat-exchange function for regulating body temperature. The artery had the well-developed internal elastic lamina and intimal cushions that regulate blood flow at the branching sites. A number of arteriovenous anastomoses were also observed between arterioles and venules, particularly in marginal regions of the ear. The intimal cushions and arteriovenous anastomoses might play an additional role in thermoregulation by regulating local blood flow in the ear.  相似文献   

4.
Collared peccary (Tayassu tajacu) belongs to the Tayassuidae family that is characterized by a dorsal scent gland located in the middle of the hump. It can be found from south-west United States to Argentina. It is a very well-adapted animal that can survive different environments, having a varied diet. Very little morphological information of the animal is available, except that concerning the reproductive tract. This study describes the histological organization of the collared peccary lip. The lip marks the junction between the integument and digestive system. It is lined by skin on the outer surface and mucosa on the inner surface. Skin appendages such as hair follicles and glands are usually found on the outer surface. The collared peccary's lip shows, on the outer surface, simple and sinus hair follicles as well as sebaceous and apocrine sweat glands. No salivary gland is found on the inner surface, and deep in the connective tissue pacinian corpuscles can be found. The connective tissue is rich in collagen and elastic fibres. The collared peccary's lip may be used not only for food prehension but also functions as a sensitive structure giving tactile input to the central nervous system.  相似文献   

5.
The distribution and arrangement of oxytalan fibres were examined in periodontal specimens of cheek teeth from seven horses. Oxidation prior to aldehyde fuchsin exposition permitted a selective staining of the oxytalan fibres, which are a distinct component of the elastic fibre system. On three horizontal levels of the periodontium--(a) subgingival, (b) middle third and (c) apical--two oxytalan fibre groups were shown histologically: 'blood vessel-related' and 'independent' oxytalan fibres. In levels a and b, both groups were arranged in a typical occluso-apical alignment along the reserve crown. Single oxytalan fibres deviated from their general course in order to attach to the cementum. In these cemental entheses the oxytalan fibres ran parallel to collagen fibre bundles. The interpretation of such morphological features emphasized the oxytalan fibres' capacity to improve the stability of periodontal blood vessel walls during masticatory movements. Level c, especially in regions next to the persisting epithelial root sheath, is the site of oxytalan fibre generation. This is a prerequisite for the facilitation of periodontal regeneration and reorganization during dental growth and eruption.  相似文献   

6.
7.
The anatomy of the auricular conchae of ruminants has been studied by intravascular injection of radiopaque latex, by dissection and by histological sectioning. Drawings were made of the vascular network. The arrangement of nerves and blood vessels in association with the ridges on the rostral (concave) surface was observed. The spaces between the ridges are relatively free of larger blood vessels, nerves, hair and sebaceous glands. This distribution is discussed in relation to the insertion of ear tags.  相似文献   

8.
The anatomy of the auricular conchae of ruminants has been studied by intravascular injection of radiopaque latex, by dissection and by histological sectioning. Drawings were made of the vascular network. The arrangement of nerves and blood vessels in association with the ridges on the rostral (concave) surface was observed. The spaces between the ridges are relatively free of larger blood vessels, nerves, hair and sebaceous glands. This distribution is discussed in relation to the insertion of ear tags.  相似文献   

9.
AIM: To determine the effect of polyester (terylene) fibre implants on normal equine superficial digital flexor (SDF) tendon structure. METHODS: Normal forelimb SDF tendons (n=24) of 12 horses were divided into unoperated, sham-operated, and implanted (terylene fibre implant) groups. Horses were assessed for lameness and ultrasonographic changes to SDF tendons at intervals up to 48 weeks post-operatively. After euthanasia, SDF tendons were collected for histological and ultrastructural examination. Histological sections were examined for alcian blue staining intensity, cellularity, fibril bundle alignment, fascicle separation and crimp morphology. Mass-average diameters (MADs) of collagen fibrils were calculated from electron micrographs and compared between treatment groups. RESULTS: Insertion of terylene fibre implants resulted in short-term (8 weeks) lameness in implanted limbs. Ultrasonographically, the implants could be detected in 50% of implanted tendons, but were associated with tendon swelling and the presence of hypoechoic core lesions in 7/8 implanted limbs. There were significant alterations in alcian blue staining, cellularity and crimp morphology in the central fascicles of sham-operated and implanted tendons, and alteration in fibril alignment in the central fascicles of implanted tendons. Unoperated tendons remained histologically normal. MADs of collagen fibrils did not differ between sham-operated, implanted and unoperated limbs. CONCLUSIONS: Both the sham procedure and the insertion of terylene fibre implants led to alterations in tendon structure that persisted for up to 48 weeks. Persistence of disorganised connective tissue at the proximal and distal ends of the terylene fibre implants may predispose implanted tendons to continued risk of injury. CLINICAL RELEVANCE: It is unlikely that terylene fibre implants offer any advantage over standard non-surgical treatments for mild to moderate cases of SDF tendonitis in the horse.  相似文献   

10.
11.
The morphology of the pancreatic duct system did not receive much attention as compared to the microanatomy of the exocrine and endocrine pancreas. The histological peculiarities of the excretory duct system are of major importance especially in laboratory animals like guinea pigs. The paper describes the histological peculiarities of the major interlobular and extrapancreatic ducts in guinea pigs. The pancreatic tissue samples were collected from five guinea pigs. For histological investigation, several pancreatic fragments underwent fixation in 10% buffered formalin and were later processed by the standard paraffin technique. Subsequentially, tissue sections were stained by Goldner's trichrome staining. The mucous substances were assessed by Alcian blue and Periodic acid–Schiff staining methods. The interlobular and main pancreatic ducts in the guinea pig present a simple columnar epithelium surrounded by a thick layer of dense connective tissue. The aforementioned epithelium of the main pancreatic ducts includes principal cells, goblet cells and basal cells. Additionally, the ductal epithelium presents occasional unicellular multiloculated intraepithelial mucous glands and prominent extraepithelial glands. The latter adopts a simple or compound tubular feature. The mucus elaborated by the three glandular types is mostly neutral in goblet cells, predominantly acidic in extraepithelial ductal glands, and a similar amount of acidic and neutral mucin in intraepithelial glands. In conclusion, the epithelium-associated mucous glands in the interlobular and main pancreatic ducts in the guinea pig are restricted not only to goblet cells. A substantial mucous discharge probably with a protecting role against irritative pancreatic juice derives from the main ductal intraepithelial and extraepithelial glands.  相似文献   

12.
为了探讨细粒棘球蚴感染羊肝脏包囊纤维化形成的病理学过程,本研究通过病理组织学、细胞化学和超微形态学的诊断方法,对羊感染细粒棘球蚴后肝脏的病理组织学变化,以及肝组织纤维化和包囊形成过程进行病理学观察。结果显示:原头蚴感染肝组织后病变沿感染组织的血管周围产生,相继出现肝细胞萎缩、变性、坏死;同时病变组织血管壁出现纤维组织分解、血管管壁出芽,增生出的纤维组织伸向周围炎症区域,血管管腔及炎区大量嗜酸性粒细胞浸润,增生的胶原纤维沿残存的肝细胞周围围绕病变组织,最终形成包囊壁。该研究结果为进一步阐释细粒棘球蚴感染羊肝脏包囊纤维化形成的病理机制奠定了坚实的基础。  相似文献   

13.
Purpose To use immunohistochemical techniques to identify and localize the structural macromolecules of the extracellular matrix (ECM) of the normal adult equine lamina cribrosa in order to make comparisons to the extracellular matrix of the lamina cribrosa of horses with glaucoma. METHODS: Normal eyes of five adult horses between 5 and 10 years of age were fixed in 10% neutral buffered formalin and embedded in paraffin. Polyclonal rabbit-derived antibodies against human elastin, laminin, fibrillin-1, and collagen types I, III and IV, and polyclonal goat-derived antibodies against collagen type VI were used as primary antibodies. Transverse and longitudinal histologic sections of the optic nerve head and lamina cribrosa were stained using several dilutions of the primary antibodies, biotinylated link antibody, horseradish peroxidase-labeled streptavidin, and 3,3'-diaminobenzidine as a chromogen. The immunohistochemical staining patterns were qualitatively interpreted. RESULTS: The normal adult horse lamina cribrosa labeled positively for collagen types I, III and VI, laminin, elastin and fibrillin. Collagen type VI staining of the laminar ECM was most intense, followed by labeling for collagen types III and I, respectively. Laminar blood vessels were weakly positive for laminin and slightly positive for type IV collagen. The scleral ECM of the laminar insertion zone had more intense labeling for collagen types I and VI than did the laminar plates. CONCLUSIONS: The extracellular matrix of the laminar plates of the adult equine lamina cribrosa is similar to the dog as it consists of elastic and collagen fibers (with collagen types VI, III and I). Both the normal dog and horse lamina display more intense staining of collagen type VI than is found in the ECM of the normal human lamina cribrosa. The macromolecular structure of the equine lamina cribrosa suggests that it is a very resilient structure that may provide some protection to the optic nerve axons during episodes of elevated intraocular pressure.  相似文献   

14.
旨在探究幼年牦牛皮肤毛囊的组织学结构和TGF-β2及HIF-1α对幼年牦牛皮肤毛囊生长发育的影响,选取10头健康幼年牦牛,采集其颈部、背部、胸部、腹部、小腿部、腋下及阴囊皮肤组织,制作石蜡切片后,采用HE和Sacpic染色,对各部位皮肤组织中毛囊进行观察和计数,并筛选出多毛及少毛部位。利用qRT-PCR、Western blot及免疫组织化学法对TGF-β2和HIF-1α在幼年牦牛多毛皮肤和少毛皮肤进行定位与定量的初步研究。结果表明,幼年牦牛皮肤的毛囊分布于真皮层,常与汗腺及皮脂腺伴行,毛髓质及内根鞘结构不完整。Sacpic染色可见毛囊内根鞘为红色,外根鞘为苍绿色,结缔组织鞘为蓝绿色。腹部皮肤的毛囊数量最多[(2 085±15)个·cm-2],阴囊数量最少[(158±15)个·cm-2]。免疫组织化学结果显示,TGF-β2及HIF-1α主要表达在表皮层、毛囊外根鞘、皮脂腺及汗腺。TGF-β2在阴囊和腋下的mRNA转录水平和蛋白质表达水平均显著高于腹部和背部。HIF-1α在腹部的mRNA转录水平和蛋白质表达水平均显著高于其他三个部位。幼年牦牛的毛囊处于退行期,在腹部数量最多,背部次之,阴囊最少;TGF-β2和HIF-1α在不同部位皮肤中的表达水平存在显著差异,为进一步研究TGF-β2和HIF-1α对牦牛皮肤毛囊生长发育的影响提供理论依据。  相似文献   

15.
In this study, we conducted a light microscopic and ultrastructural analysis of the integument of the one-humped camel (Camelus dromedarius). In general, the epidermal strata of the camel integument appeared typical of those found in non-desert mammals. Two cell populations were noted in the stratum basale: one with a flat, non-serrated base and the other with a highly serrated base. Typical fine structure was observed in keratinocytes of the stratum spinosum and stratum granulosum. The stratum corneum was six to 10 cells thick. Within the different strata, overall cell morphologies and the general distribution and relative abundance of cellular organelles appeared typical. Dermal features included the presence of myoepithelial cells surrounding apocrine tubular glands. Inter- or intracellular canaliculi within the secretory cells of the apocrine glands, reported to be present in certain other non-desert mammals, were not evident in the camel. Together, these data indicate that while the camel is clearly adapted for a desert lifestyle, these adaptations do not include significant specializations at the cellular or subcellular level in the integument.  相似文献   

16.
Skin lesions were established on the flanks of pigs aged 10 to 12 weeks, in the areas of the ribs, the mid-upper leg, the shoulder and the tuber ischii. Skin lesions on the ear tips, known as porcine necrotic ear syndrome, were detected in weaners throughout the raising period. By the histological examination of 50 samples of skin lesions from the flank, two stages of epidermal and dermal changes were established; the milder stage had epidermal changes with marked acanthosis, rete ridges formed deep in the dermis and mild infiltrates of mononuclear cells in the layers around the capillaries in the dermis; the more severe stage had ulcers, under which there were infiltrates of polymorphonuclear cells. The same histological changes were observed in 23 samples of skin lesions taken from the tips of ears with necrotic ear syndrome. On healthy skin from the flank and ear tip, micrococci were the dominant organism, whereas on skin lesions from both the affected areas staphylococci were dominant. Since the histological lesions on the flanks were identical to those in necrotic ear syndrome, which has been associated with Staphylococcus hyicus infection, the pathogenesis of the lesions on the flanks is probably the same.  相似文献   

17.
为探明高产与低产乌鸡主要生殖器官的组织学特点差异,采用石蜡切片、HE染色方法对高产与低产泰和乌鸡主要生殖器官———卵巢及输卵管子宫部结构特点进行比较。结果表明,高产组乌鸡卵巢内生长卵泡多,卵泡外腺细胞数量少,输卵管子宫部皱襞长呈叶片状,固有膜内管状腺发达,血管、神经丰富;低产组乌鸡卵巢内初级卵泡数量较多,次级卵泡量少,卵泡外腺细胞数量较多,输卵管子宫部皱襞较短,血管少。结果还表明,高产组乌鸡主要生殖器官的组织结构与低产乌鸡的差异较大,说明高产组乌鸡的主要生殖器官发育完善,功能较强。  相似文献   

18.
Background: Ehlers-Danlos syndrome comprises a group of rare inherited connective tissue diseases characterized by skin hyperextensibility, joint laxity, skin and vessel fragility, and poor wound healing.
Objective: The purpose of this report was to describe the clinical, histologic, and ultrastructural findings in 2 dogs with collagenopathies consistent with Ehlers-Danlos syndrome.
Methods: Two dogs were examined clinically; skin extensibility index was calculated. Skin biopsies obtained from the dorsum were examined by light and electron microscopy.
Results: Both dogs had clinical signs of skin hyperextensibility and fragility, lower skin elasticity, vessel fragility, and poor wound healing. One dog had a hip dislocation, and the other had bilateral medial patellar luxation (grade II), subcutaneous hematomas produced by minimal trauma, and generalized periodontitis. Histologic and ultrastructural examination confirmed abnormalities in the structure and arrangement of collagen fibrils. Fibroblasts were characterized by variable dilatation of the rough endoplasmic reticulum, and anomalous elastic fibers (elaunin fibers) were present in the dermis.
Conclusion: Although the primary defects underlying collagenopathies in animals are still unknown, analysis of the ultrastructural changes in collagen fibrils and clinical findings could facilitate better characterization of these disorders in dogs.  相似文献   

19.
Monoclonal antibodies against Desmoplakin and Plakoglobin were tested for their suitability as specific markers of lymphatic vessels. The tissue samples were taken from horse skin in an attempt to establish the horse as a model for human lymphatic diseases. To obtain a clear, positive identification of blood and lymphatic vessels, immunohistochemical staining with antibodies against vascular endothelial growth factor receptor 3 (VEGFR-3) and platelet endothelial adhesion molecule (PECAM-1, CD31), was compared with Desmoplakin and Plakoglobin. Because anti-VEGFR-3 is specific for lymphatic vessels in the skin while anti-CD31 stains blood and lymphatic vessels as well, it can be concluded that VEGFR-3(-)/CD31(+) vessels are blood vessels and VEGFR-3(+)/CD31(+) vessels are lymphatic vessels. It was documented on serial sections that Plakoglobin stains both blood and lymphatic vessels. However, Desmoplakin did not stain several positively identified lymphatic vessels. Therefore, Desmoplakin and Plakoglobin antibodies are not specific markers of lymphatic vessels in the skin and the staining pattern is tissues and species dependent.  相似文献   

20.
为了揭示羊驼皮肤胶原蛋白(Collagen)在皮肤结构发生中的分子机制,本研究通过构建羊驼皮肤cD—NA文库并进行大规模测序分析,结果表明:在羊驼皮肤内发现只有纤维类胶原表达,即typeⅠ,typeⅢ,typeⅤ collagen,其中typeⅠ表达最高,typeⅢ和typeⅤ表达低;然而,在羊驼皮肤内未发现各类collagen相对应的原胶原(procollagen),其成员procollagentype Ⅰ,typeⅢ,typeⅣ,typeⅥ,typeⅦ,typeⅩⅧ在表达,且typeⅠ远远高于其他家族成员的表达,由此推断collagen和procollagentypeⅠ在羊驼皮肤结构发生中起主要作用,羊驼皮肤内的蛋白水解机制可能使procollagen产生不同类型的collagen。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号